Rhizobium and Mycorhizal fungi – two kingdoms to improve the third.

One of the more frequent questions we are asked by farmers and distributors is “What microbial bio stimulant should we apply to our legume seeds, Rhizobium or Mycorrhiza?” My answer is clear: “both”. They are complementary and very different organisms, and come from different kingdoms (fungi and Bacteria). Rhizobia are soil bacteria known for fixing nitrogen inside legume root nodules. Arbuscular mycorrhizal (AM) fungi are ubiquitous root symbionts that provide plants with nutrients and other benefits. There are dozens of scientific papers that prove that both organisms are beneficial and complementary. For example, Wang et al. in 2011 demonstrated that co-inoculation of soybean with rhizobia and AM fungi significantly increases soybean growth, increasing shoot dry weight, along with plant N and P content, and the plant nodulation. Furthermore, the effects of co-inoculation were related to root architecture. Last year, (Meena et al, 2018) verified that the regulatory response and interaction of Bradyrhizobium and arbuscular mycorrhizal fungi (AMF) play a vital role in rhizospheric soil processes and productivity of soybean (Glycine max L.). He proved that Nitrogen (N) and phosphorus (P) are essential nutrients for plant growth and productivity, and that the synergistic interaction(s) of AMF and Bradyrhizobium along with rhizospheric beneficial microorganisms stimulate soybean growth and development through enhanced mineral nutrient acquisition (N and P) and improved rhizosphere environment.

Such interactions are crucial, but not just in organic agricultural cropping systems, which rely on biological processes rather than agrochemicals to maintain soil quality, sustainability, and productivity, but also in any sustainable farming system that aims to improve the efficiency of the inputs increasing the productivity, the health of the soils and the sustainability of the agrosystem. Furthermore, enhancement of N-fixation by root nodules along with AMF-mediated synergism improves plant P nutrition and uptake, and proliferation of phosphate-solubilizing fungi.

Another benefit that is demonstrated and observed in several field trials, is the drought tolerance that the mycorrhizas exert in the crops. Porcel et al. (2004) showed that mycorrhized soybeans were protected against drought, as shown by their significantly higher shoot-biomass production. Mycorhizal fungi also helps rhizobium inside the nodules. Ruiz Lozano  (2001)  proved that this  symbiosis can alleviate drought‐induced nodule senescence in soybean plants.

These are a few more examples of the dozens of scientific papers published over recent years, demonstrating the efficacy of the combination of both beneficial organisms for the legumes.

Legume Technology does offer a high quality Rhizobium for seed coating legume crops (Legumefix and Liquifix) and the complementary and compatible Mycofix; a mix of Mycorhizal fungi and 100% soluble seaweed (also compatible with seed coating), selected to maximize the yield of legumes, thanks to the natural synergy of both crops.

 

Dr. Daniel García-Seco, R&D Manager at Legume Technology, is Agronomist and Doctor cum laude in Biotechnology of the Rhizosphere, with  more than 12 years of experience developing projects about new biostimulants for academy and industry in Spain, France and UK.

 

Is it possible to naturally improve the grain quality in a legume?

The grain quality of a legume is evaluated with multiple parameters such as protein content, oil content, amino acid balance, weight and volume of 100 grains, cooking time or lignin content and similar.

Traditionally, the only way to increase the quality of the grains was to throw genetic improvement of cultivars, a slow and difficult system. More recently, synthetic fertilizers appear as another tool to increase the yield and quality, but they are not always the most environmental-friendly solutions.

Legumes (soybean, chickpea, alfalfa, etc.) have a fantastic and almost a unique property: they can associate with a bacteria (Rhizobium) to fix huge amounts of atmospheric nitrogen, making needless to fertilize with synthetic nitrogen.

Thanks to this plant-microbe association, called symbiosis, any farmer worldwide can improve the yield and quality of their production using a high-quality inoculant on the seeds.

Coating the seeds with the correct amount of the appropriate strains of Rhizobium improves not just the yield, also the quality of the final product. It has been broadly scientifically demonstrated that the application of the correct inoculum improves the protein content and the oil content of the seeds.

In the figure below there is an example of a field trial in soybean in 2018 where an increase of the yield and seed quality was observed.

Fig.1 Soybean Field trials 2018 (Guelph University, Canada).

But this broadly demonstrated benefit of the rhizobium quality has been extended to other parameters, such as nutraceuticals. For example,  Andrade et al. 2013 demonstrated that the inoculation of soybean with Bradyrhizobium japonicum is a beneficial agricultural practice not only to increase the production of this legume, but to enhance its nutraceutical potential overall. These complementary beneficial microbes will help next year crops, together with the nitrogen that will remain in the soil, due to the Nitrogen fixation of the legume-rhizobium association.

 

 

 

 

Therefore, it is safe to say that the application of high-quality inoculants to legumes seeds is the faster, cheaper, cleaner and smarter way to improve the quality of the crops.

 

 

Dr. Daniel García-Seco, R&D Manager at Legume Technology, is Agronomist and Doctor cum laude in Biotechnology of the Rhizosphere, with  more than 12 years of experience developing projects about new biostimulants for academy and industry in Spain, France and UK.

 

 

6 reasons to apply rhizobium to my soybean seeds

1.The only way to reach all the genetic potential of soybeans.

It is scientifically demonstrated that Bradyrhizobium japonicum is a natural symbiont of Soybean. Thanks to a synergistic evolution over thousands of years there is a perfect symbiosis whereby the plant builds a “house” for the bacteria in the roots (the nodules) and the bacteria fix atmospheric Nitrogen directly inside the plant. It is not possible to reach this potential using synthetic Nitrogen fertilisers.

2. More yield benefit and better quality.

By inoculating the seeds with high quality inoculants, the natural microbial population of the soil will be improved, therefore the plants will be colonised by the best strains in correct numbers, maximising the yield and the quality of your soybean.

  1.  Healthier for the soil.

Thanks to the elimination of synthetic nitrogen fertilisers, not only rhizobium, but also other beneficial microbes can repopulate the soil, improving the natural microbiota. It is demonstrated that the nitrogen content of the soil increases even the year after the inoculated soybeans were harvested (around 40 kg of N / ha), helping your crops in the following season.

  1. Environmentally friendly.

There is a significant evidence that the abuse of the synthetic nitrogen fertilisers provokes the eutrophication of the rivers, lakes and seas, and contributes to the extinction of aquatic life in the ecosystem. Thanks to the substitution of these chemicals by natural nitrogen fixation we can positively impact the ecosystem.

  1. Greater economic value.

The application of a good rhizobium-based inoculant is much more cost effective than any application of synthetic nitrogen to your soil.

  1. No increased health risks for you and others.

High solubility of nitrate in water and its low retention by soil particles make it a major component of groundwater in areas of high nitrate formation. Nitrate enters the human body by groundwater used for drinking and causes health disorders, namely, methemoglobinemia, gastric cancer, birth malformations, hypertension, etc., when present in high concentration in drinking water. Substituting the synthetic fertilisers with Rhizobium seed inoculation

Legume Technology has taken all of these reasons into account during the production process and proudly offers high quality and environmentally friendly inoculants, suitable for all major legume crops – LegumeFiX and LiquiFiX.

 

Dr. Daniel García-Seco, R&D Manager at Legume Technology, is Agronomist and Doctor cum laude in Biotechnology of the Rhizosphere, with  more than 12 years of experience developing projects about new biostimulants for academy and industry in Spain, France and UK.